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<li><a href="#synopsis_usage_and_example">Usage and example</a>
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<li><a href="#synopsis_usage">Usage</a></li>
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        <h2>Usage and example<span><a class="mark" href="#synopsis_usage_and_example" id="synopsis_usage_and_example">#</a></span></h2>
<section><h3>Usage<span><a class="mark" href="#synopsis_usage" id="synopsis_usage">#</a></span></h3>


<p><code>node [options] [V8 options] [script.js | -e "script" | - ] [arguments]</code></p>
<p>Please see the <a href="cli.html#cli_command_line_options">Command-line options</a> document for more information.</p>
</section><section><h3>Example<span><a class="mark" href="#synopsis_example" id="synopsis_example">#</a></span></h3>
<p>An example of a <a href="http.html">web server</a> written with Node.js which responds with
<code>'Hello, World!'</code>:</p>
<p>Commands in this document start with <code>$</code> or <code>></code> to replicate how they would
appear in a user's terminal. Do not include the <code>$</code> and <code>></code> characters. They are
there to show the start of each command.</p>
<p>Lines that don’t start with <code>$</code> or <code>></code> character show the output of the previous
command.</p>
<p>First, make sure to have downloaded and installed Node.js. See
<a href="https://nodejs.org/en/download/package-manager/">Installing Node.js via package manager</a> for further install information.</p>
<p>Now, create an empty project folder called <code>projects</code>, then navigate into it.</p>
<p>Linux and Mac:</p>
<pre><code class="language-console"><span class="hljs-meta">$ </span><span class="language-bash">mkdir ~/projects</span>
<span class="hljs-meta">$ </span><span class="language-bash"><span class="hljs-built_in">cd</span> ~/projects</span></code></pre>
<p>Windows CMD:</p>
<pre><code class="language-console"><span class="hljs-meta">> </span><span class="language-bash">mkdir %USERPROFILE%\projects</span>
<span class="hljs-meta">> </span><span class="language-bash"><span class="hljs-built_in">cd</span> %USERPROFILE%\projects</span></code></pre>
<p>Windows PowerShell:</p>
<pre><code class="language-console"><span class="hljs-meta">> </span><span class="language-bash">mkdir <span class="hljs-variable">$env</span>:USERPROFILE\projects</span>
<span class="hljs-meta">> </span><span class="language-bash"><span class="hljs-built_in">cd</span> <span class="hljs-variable">$env</span>:USERPROFILE\projects</span></code></pre>
<p>Next, create a new source file in the <code>projects</code>
folder and call it <code>hello-world.js</code>.</p>
<p>Open <code>hello-world.js</code> in any preferred text editor and
paste in the following content:</p>
<pre><code class="language-js"><span class="hljs-keyword">const</span> http = <span class="hljs-built_in">require</span>(<span class="hljs-string">'http'</span>);

<span class="hljs-keyword">const</span> hostname = <span class="hljs-string">'127.0.0.1'</span>;
<span class="hljs-keyword">const</span> port = <span class="hljs-number">3000</span>;

<span class="hljs-keyword">const</span> server = http.<span class="hljs-title function_">createServer</span>(<span class="hljs-function">(<span class="hljs-params">req, res</span>) =></span> {
  res.<span class="hljs-property">statusCode</span> = <span class="hljs-number">200</span>;
  res.<span class="hljs-title function_">setHeader</span>(<span class="hljs-string">'Content-Type'</span>, <span class="hljs-string">'text/plain'</span>);
  res.<span class="hljs-title function_">end</span>(<span class="hljs-string">'Hello, World!\n'</span>);
});

server.<span class="hljs-title function_">listen</span>(port, hostname, <span class="hljs-function">() =></span> {
  <span class="hljs-variable language_">console</span>.<span class="hljs-title function_">log</span>(<span class="hljs-string">`Server running at http://<span class="hljs-subst">${hostname}</span>:<span class="hljs-subst">${port}</span>/`</span>);
});</code></pre>
<p>Save the file, go back to the terminal window, and enter the following command:</p>
<pre><code class="language-console"><span class="hljs-meta">$ </span><span class="language-bash">node hello-world.js</span></code></pre>
<p>Output like this should appear in the terminal:</p>
<pre><code class="language-console">Server running at http://127.0.0.1:3000/</code></pre>
<p>Now, open any preferred web browser and visit <code>http://127.0.0.1:3000</code>.</p>
<p>If the browser displays the string <code>Hello, World!</code>, that indicates
the server is working.</p></section>
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